books.google.com.ph - "Publications of the Academy of Natural Sciences of Philadelphia": v. 53, 1901, p. 788-794....http://books.google.com.ph/books/about/Proceedings_of_the_Academy_of_Natural_Sc.html?id=G3jIkWiEwsMC&utm_source=gb-gplus-shareProceedings of the Academy of Natural Sciences of Philadelphia